Method of casting and pattern therefor



May 5, 1931.

C. HANKINS METHOD OF CASTING AND PATTERN THEREFOR 2 Sheets-Sheet 1- Original Filed Nov. 20, 1925.

time/"tom y 5, 1931. c. HANKINS 1,803,551

METHOD OF CASTING AND PATTERN THEREFOR Original Filed Nov. '20, 1925 2 Sheets-Sheet 2 INVENTOR ATTORNEY Patented May 5, 1 931 outrun s'rAr s PATENT orrics CYRUS HANKINS, OF BALTIMORE, MARYLAND, ASSIGNOBTO THE S YMINGTON COIL.

PALNY, OF NEW YORK, N. Y., A CORPORATION OF MARYLAND METHOD OF CASTING- AND RATTERN THEREFOR Original application filed November 20, 1925, Serial No. 70,274. Divided and this application filed November 18, 1926. Serial No. 149,118.

This application is a division of my copend ing application Serial No. 70,274, filed November'20, 1925, now Patent No. 1,637,696, dated August 2, 1927.

The invention relates to a method of casting any article from molten metal and the patterns therefor having particular reference to the manufacture of cast steel side frames.

The principal object of my invention, generally considered, is the manufacture of castings and particularly those in which it is necessar to use baked cores positioned in a mould 0 green sand, the strength of said castin s being increased, internal coolin strains re need and weaknesses ordinarily found at portions of the'metal cast adjacent the junction between the green sand mould and baked core or. cores bemg minimized by my improved method of casting.

An object of m invention is the improvement in the met od of casting articles in which cores are used for producing extensions thereon, said method involving the limitation of substantially transverse lines of weakness between portions of the cast metal at the junction in the mould between a baked core and greemsand, said usual transverse lines being arranged to extend diagonally or at an inclination to increase the strength of the casting. i

Another object of my invention is the improvement in the strength of castings and particularly sideframes for. railway car trucks in which cores are used for forming external depending flanges or webs on the tension member thereof, for example, said articles being producedvby a method involving the limitation of substantially transverse lines of weakness between metal cast, respectively, ad acent a baked core set in a corresponding portion of a mould and the green sand of said mould, and the substitution for such lines of weakness of corresponding lines extending diagonally rather than transversely across the casting to materially increase the strength thereof at such oints.

A urther objecto m vision of patterns an cores of improved construction for forming castings to obviate ortions of the invention is the pro-' Figure 1 1s a side elevation, partly-in vertical section on the longitudinal center line of a side frame constructed in accordance with my invention, the core print extensions for the patterns thereof being indicated diagrammatically by dot and dash lines.

Fi re 2 is a transverse sectional view on the line 22 of Figure 1.

Figure 3 is a side view of "that portion of a pattern for forming the mould to cast a diagonal end portion of the tension member of the side frame, showing particularly core print forming projections constructed in accordance with my invention.

Figure 4 is a side elevation of a fragmentary portion of the pattern used for casting side frame;

Figure 5 is a side elevation of one of the cores corresponding to the fragmentary portion of the pattern illustrated in Figure 4. said core being shown in place in the mold. Figure 6 is a plan of the core shown in Figure'5 in place in the mold.

Figure 7 is a transverse sectional view on the line 77 of Figure 6, looking in the direction of the arrows.

Referring to the drawings in detail, like parts being designated by like reference characters, there is illustrated a side frame such as shown in my Patent N). 1,637,696 of August 2, 1927. Said side frame is illustrated merely for the purpose of showing my improved method of manufacture and particularly that part of the method involving the formation of external flanges such as designated by'the reference character 19, said flanges, in the.

window openings 14 is preferably reinforced by depending flanges 19. The depth of these flanges. is preferably a maximum substantially coincident with the intersection of the web of the tension member by diagonal lines drawn from the lower corners of the window opening. These flanges 19 are preferably reinforced adjacent the lower or marginal edges thereof by. beading or lips 20.

Adjacent each end of the frame and in the present embodiment formed integral therewith is a journal box 21, the lower web 7 of said tension member 2 preferably meeting and merging with the roofs 22 of said journal boxes and the flanges or side walls 5 of the compression member 1 preferably being continued to merge with the roofs 22 of said boxes as illustrated. As additional reinforcements between the tension member and the journal boxes, connecting web portions 23 are preferabl provided between the lower face or web 7 o the tension member and the adjacent walls 24 of the journal boxes, said web portions 23extending longitudinally and spaced apart as illustrated, the upper and lower edges of said portions preferably being strengthened by beading or ribs 25 extending therealong. The upper edges of said reinforcements 23 are preferably spaced from the point of union 26 between the web 7 of the tension member and the adjacent journal box 21, thereby forming substantially triangular openings 27.

Although I have described certain features of a side frame preferably formed with integral journal boxes 21 and constructed of cast steel, it will be apparent that the method of casting such an article to be now described is equally well adapted for constructing other articles of cast metal of any desired character so that the foregoing description of the article to be cast should be considered merely as illustrative and not limiting.

Referring now particularly to Figures 3 and 4, there is illustrated a portion of the pattern utilized for casting a frame constructed in accordance with my invention. In order to form the flanges 20 and the connecting web 23, it is necessary to have core print portions 28, 29, 30 and 31 on the pattern parts 32 and 33. As illustrated, the drag or lower side 33 of the pattern has the core print portions 29 and 31 thereon and the cope or upper side 32 has similar registering core print portions 28 and 30 thereon. These core prmtortions, and the corresponding core 39, see ig ures 5, 6 and 7, have their ends 34 tapered or extended on diagonal lines, as illustrated, so that the junction 37 between the green sand used for forming the main part mould 38 and the baked core 39 inserted in the core prlnts extends along diagonal lines rather than along a substantially transverse line, with just enough draft provided for the withdrawal of the pattern from the mould.

of the are likewise provided for forming the reinforcing webs 23 between the tenslon memher and adjacent journal box. It will be obvious, however, that in casting other articles besides side frames where baked sand cores are used in a similar way to form projections or reinforcements, the patterns are constructed to correspond or, in other words, a similar method is employed for accomplishing the desired result even though the casting roduced may be of a shape very different from that illustrated.

As well known to those skilled in the art, the junction between the metal cast adjacent a baked core and that cast adjacent the green sand is very imperfect and relatively Weak, not only because of the difference in molecular structure of the metal, but because of the offset commonly formed due to not properly matching cores in the mould. The usual way to end a core print and its corres onding core is indicated by the dot and dash ines extending substantially transversely or vertically between the upper and lower edges of the core prints. The top views of the core prints are indicated diagrammatically in Figure 1 by dot and dash lines. When side frames are cast utilizing patterns with core prints as illustrated, the line of imperfect metal along the bottom or web 7 of the diagonal tension ortion of the side frame extends along iagonal or broken lines corresponding with the. tapered ends of the core prints rather than substantially directly across the web 7 of said tension member, thereby prolonging the length of the imperfect metal between the baked core and green sand mould and extending it over a substantial length of the tension member so that only a small portion of imperfect metal is found in any given section through the tension member.

By virture of my improved method of casting and improved patterns and cores, which method as will be obvious is adapted for casting other articles where cores are emplo ed as well as side frames, eatly improve strength may be effected in said articles, especially portions thereof normally in tension. 1

Having now described my invention, I claim:

1. The method of casting, where cores are employed to secure external flanges, comprising forming a attern with core print portions havin ta ered along the exterior surface of t e moldorming part thereof, in-

serting correspondingly constructed cores in the core prints formed whereby, when the article is cast, the/strength of the casting adjacent the junction between the core and mould is improved.

2. The method of casting involving the formation of the junction line in the mould, along the surface'of the metal receiving portion thereof, between thegreen sand and a baked core held in said sand, on a diagonal rather thanon a substantially transverse line between the sides of the mould.

3. The method of casting comprising forming the lower half of'a pattern with a core print portion, the ends of which slope upwardly and outwardly,- forming the upper half of said pattern with registering core print portions, the ends of which slope downwardly and outwardly, forming a mould with said pattern, and inserting a corresponding core in the core prints formed whereby, when an article is cast in said mould, the line formed between the metal adjacent the sand of the mould and the baked core therein,will extend diagonally rather than transversel or vertically.

4. The metho of casting side frames for railway car trucks comprising forming the drag side of the pattern with a core print portion, the ends of which slope upwardly and outwardly, forming the cope side of the pattern with corresponding core print portions, the ends of which slope downwardly and outwardly, forming amould with said pattern, and inserting a corresponding core in the core prints formed whereby, when metal is cast in said mould, the line formed between the metal adjacent the sand of the mould and the baked core therein will extend diagonally rather than substantially transversely.

5. A pattern for casting, formed with core print portions extending therefrom, the ends of said core print portions tapering along a mould-forming wall thereof toward the parting line ofthe pattern.

6. A pattern for casting comprising a main portion with core print extensions therefrom and longitudinal continuati'ons from said core print extensions, said continuations decreasing in depth along a mould-forming wall toward the parting line of the pattern.

7. A core for casting formed with ends pointed or tapered along a mould-forming surface thereof and adapted for reception in corresponding core prints in a mould whereby the usual lines of weakness in the casting at the junctions between the core and green sand are made to extend diagonally or inclined rather than directly across the casting. In testimony whereof I aflix my signature.

CYRUS HANKINS'. 

